JP6191516B2 - Engine loss torque learning device - Google Patents

Description

  The present invention relates to an apparatus for learning engine loss torque.

  In order to control the output torque of the engine (torque generated on the crankshaft), it is necessary to consider engine loss torque (torque loss). Loss torque is caused by pumping loss (intake / exhaust loss) and friction loss (friction loss) of the engine, but changes every moment due to factors such as engine operating conditions such as cooling water temperature, individual engine differences, and changes over time. . For this reason, in order to increase the accuracy of torque control of the engine, it is necessary to learn the loss torque as appropriate. In the conventional engine control device, the learning of the loss torque is performed during the idling operation of the engine while the engine is warmed and the vehicle is stopped (for example, refer to Patent Document 1).

  Further, in recent years, a function of idle stop control (automatic stop start control) is widely used in vehicles, in which an engine is automatically stopped when an automatic stop condition is satisfied and thereafter an engine is automatically started when an automatic start condition is satisfied.

JP 2007-278293 A

  In the conventional technique, it is necessary to keep the engine in an operating state (idle operating state) until the process for learning the loss torque is completed. For this reason, it may be necessary to prohibit the automatic stop of the engine by the idle stop control, resulting in deterioration of fuel consumption.

  Accordingly, an object of the present invention is to provide an engine loss torque learning device that does not affect idle stop control.

  A vehicle in which the engine loss torque learning device of the first invention is used includes an idle stop control means. The idle stop control means automatically stops the engine when a predetermined automatic stop condition is satisfied, and then automatically starts the engine when a predetermined automatic start condition is satisfied.

The engine loss torque learning device according to the first aspect of the present invention comprises illustrated torque storage means, torque detection means, and loss torque calculation means.
The indicated torque storage means stores the indicated torque of the engine when the engine is started. The torque detecting means detects a crankshaft generated torque that is a torque generated on the crankshaft of the engine at the time of starting the engine, and the loss torque calculating means detects the indicated torque stored in the indicated torque storage means and the torque detection. The difference from the crankshaft generated torque detected by the means is calculated as engine loss torque.

  According to this engine loss torque learning device, the loss torque calculated by the loss torque calculation means can be stored in a memory or used for engine control as a loss torque learning value. And since the process for learning loss torque is performed at the time of engine starting, it is not necessary to prohibit the engine automatic stop by idle stop control. For this reason, the execution of the idle stop control is not affected. Further, since the loss torque can be learned every time the engine is automatically stopped by the idle stop control and restarted while the vehicle is being used, a sufficient learning frequency can be ensured.

  In addition, the code | symbol in the parenthesis described in the claim shows the correspondence with the specific means as described in embodiment mentioned later as one aspect, Comprising: The technical scope of this invention is limited is not.

It is a block diagram showing the structure of the electronic controller (ECU) of 1st Embodiment. It is explanatory drawing explaining a throttle. It is a flowchart showing an idle stop control process. It is explanatory drawing explaining an effect | action of an electronic control apparatus. It is a flowchart showing the loss torque learning process of 1st Embodiment. It is a flowchart showing the blowing up suppression process of 2nd Embodiment. It is a flowchart showing the loss torque learning process of 2nd Embodiment.

  Hereinafter, an electronic control device according to an embodiment to which the present invention is applied will be described. An electronic control device (hereinafter referred to as ECU) of the present embodiment controls an engine (internal combustion engine) mounted on a vehicle and an auxiliary machine of the engine.

[First Embodiment]
As shown in FIG. 1, in a vehicle 3 on which the ECU 1 of this embodiment is mounted, torque generated on the crankshaft 7 of the engine 5 (that is, output torque of the engine 5) is a transmission (in this embodiment, an automatic transmission). ) Is transmitted to four wheels 11 to 14 through 9. In this example, the vehicle 3 is a four-wheel drive vehicle. However, if the vehicle 3 is a front-wheel drive vehicle, the output torque of the engine 5 is transmitted only to the front wheels 11 and 12 among the wheels 11 to 14, and the rear-wheel drive vehicle. If there is, the output torque of the engine 5 is transmitted only to the rear wheels 13 and 14 among the wheels 11 to 14.

  The ECU 1 includes a microcomputer 21 that controls the operation of the ECU 1, an input circuit 23 for taking in a signal from the outside of the ECU 1, an output circuit 25 for outputting a signal to the outside of the ECU 1, Is provided.

  The input circuit 23 receives the crank angle signal from the crank angle sensor 31 for detecting the crank angle that is the rotation angle of the crankshaft 7 and the engine speed, the cylinder discrimination signal from the cam angle sensor 32, the vehicle speed (vehicle 3), the vehicle speed signal from the vehicle speed sensor 33, the accelerator signal from the accelerator sensor 36 for detecting the amount of operation of the accelerator pedal 35 by the driver of the vehicle 3, and the brake pedal 37 being depressed by the driver. A brake signal from the brake sensor 38 for detecting the occurrence of the event, a user start signal from a start switch 39 operated when the driver wants to start the engine 5 at his own will, and a throttle 41 of the engine 5 (see FIG. 2). ) For the control of the engine 5 such as a signal from a throttle opening sensor 42 for detecting the opening (hereinafter also referred to as throttle opening). The principal various signals, is input to the microcomputer 21.

  The output circuit 25 outputs a drive current for causing the injector 43 to inject fuel according to a control signal from the microcomputer 21, outputs an ignition signal for causing the igniter 44 to perform ignition, A drive current is output to a starter 45 that cranks the engine for starting, a drive current is output to a throttle motor 46 that adjusts the opening of the throttle 41, and an alternator 47 driven by the engine 5 has a power generation capability (power generation Output the excitation current to adjust the amount).

  The injector 43 and the igniter 44 are provided for each cylinder of the engine 5 in this embodiment, but only one set is shown in FIG. As shown in FIG. 2, the throttle 41 is provided upstream of the surge tank 52 in the intake manifold 51 of the engine 5, and the opening degree is adjusted by the throttle motor 46. That is, the throttle 41 and the throttle motor 46 constitute a so-called electronic throttle 53. In FIG. 2, “54” is a piston that reciprocates within the cylinder 55 of the engine 5, “56” is an intake valve, and “57” is an exhaust valve.

  Returning to FIG. 1, the microcomputer 21 includes a CPU 61 that executes a program, a ROM 62 that stores a program executed by the CPU 61, data that is referred to when the program is executed, and a RAM 63 that stores a calculation result by the CPU 61. , A nonvolatile memory (for example, a flash memory or an EEPROM) 64 capable of rewriting stored contents, an A / D converter (ADC) 65, and an input / output port (I / O) 66. In addition, the indicated torque storage unit 62 a which is a part of the storage area of the ROM 62 stores the indicated torque of the engine 5.

  Next, processing performed by the CPU 61 of the microcomputer 21 will be described. Note that the processing performed by the CPU 61 is realized by a program in the ROM 62. Further, when the vehicle is in an ignition-on state and the battery voltage (the voltage of the on-vehicle battery) is supplied to the ECU 1 as the operation power supply, the microcomputer 21 supplies a constant power supply voltage (for example, 5 V) from a power supply circuit (not shown). Is supplied and activated. The ignition on state is a state in which the battery voltage is supplied to the ignition system power line in the vehicle. For example, when the ignition switch of the vehicle is turned on, the vehicle is in an ignition-on state.

  The CPU 61 performs an injection control process for controlling fuel injection from the injector 43, an ignition control process for controlling ignition by the igniter 44, and a throttle control process for controlling the throttle opening, as processes for bringing the engine 5 into an operating state. And do.

  Further, the CPU 61 performs a user start process for starting the engine 5 in response to a driver start operation (in this embodiment, an operation to turn on the start switch 39), and automatic stop / automatic restart of the engine 5. An idle stop control process for realizing the idle stop control function, a torque control process for the engine 5, a power generation control process for the alternator 47, and a loss torque learning process for learning the loss torque of the engine 5 are also performed.

<User start processing>
When the CPU 61 detects that a user start signal from the start switch 39 has been input after being started, the CPU 61 performs a user start process.

  As a user start process, the CPU 61 first operates the starter 45. Then, the engine 5 is cranked by the starter 45, and the CPU 61 controls the throttle opening to a predetermined opening for starting the engine by the throttle control process, and the fuel injection and ignition to the engine 5 by the injection control process and the ignition control process. Will be carried out.

  When the CPU 61 determines that the engine 5 is in a complete explosion state (starting is complete, so-called engine 5 is applied) based on the engine speed calculated from the crank angle signal, the starter 45 Stop the operation. The user start is to start the engine 5 in response to the driver's start operation.

<Idle stop control processing>
The CPU 61 executes the idle stop control process of FIG. 3 at regular time intervals, for example.
As shown in FIG. 3, when starting the execution of the idle stop control process, the CPU 61 first determines in S110 whether or not the engine 5 is in operation based on, for example, the engine speed, If in operation, the process proceeds to S120.

  In S120, the CPU 61 determines whether or not an automatic stop condition is satisfied. The automatic stop condition is, for example, that all the following conditions are satisfied. The brake pedal 37 is depressed. The accelerator pedal 35 is not depressed (the operation amount of the accelerator pedal 35 is 0). The vehicle speed is not more than a predetermined value (for example, 5 km / h).

  When the CPU 61 determines that the automatic stop condition is satisfied, the CPU 61 proceeds to S130 and performs a process of automatically stopping the engine 5. As the process, for example, the fuel injection from the injector 43 is stopped. Further, for example, the throttle opening may be set to zero.

  If the CPU 61 stops the engine 5 in S130 or determines that the engine 5 is not operating (the engine 5 is stopped) in S110, the CPU 61 proceeds to S140 and is in idle stop. It is determined whether or not. The idling stop is a state in which the engine 5 is automatically stopped by the process of S130.

  If the CPU 61 determines that the idle stop is being performed, the CPU 61 proceeds to S150 and determines whether or not the automatic start condition is satisfied. The automatic start condition is, for example, that any of the following conditions is satisfied. The brake pedal 37 was released. The accelerator pedal 35 was depressed (the amount of operation of the accelerator pedal 35 is no longer 0).

  If it is determined that the automatic start condition is satisfied, the CPU 61 proceeds to S160 and performs a process of automatically starting (that is, automatically restarting) the engine 5. As the processing, for example, the same processing as the above-described user starting processing is performed.

Then, the CPU 61 thereafter ends the idle stop control process.
The CPU 61 determines that the automatic stop condition is not satisfied in S120, or determines that the idle stop is not being performed in S140, or the automatic start condition is satisfied in S150. If it is determined that it is not, the idle stop control process is terminated as it is.

  By such an idle stop control process, for example, if an automatic stop condition is satisfied at time t0 in FIG. 4, the engine 5 is automatically stopped as shown at time t1. If the automatic start condition is satisfied at time t2 in FIG. 4, the engine 5 is automatically restarted. The “brake on period” in FIG. 4 is a period during which the brake pedal 37 is depressed. Further, the “idle stop period” in FIG. 4 is a period during which the engine 5 is stopped by the idle stop control (automatic stop period).

<Torque control processing>
The CPU 61 determines the target output torque of the engine 5 (target torque to be generated on the crankshaft 7) from the request information indicating the driver's request (for example, the operation amount of the accelerator pedal 35) and the operation information such as the engine speed. . Then, the CPU 61 sets the fuel injection amount, fuel injection timing, ignition timing, and throttle opening for realizing the target output torque as control target values for the injection control process, the ignition control process, and the throttle control process.

  Further, the CPU 61 determines the target output torque in consideration of a loss torque learning value of the engine 5 (hereinafter also referred to as a loss torque learning value). From the viewpoint that the torque actually generated in the crankshaft 7 is reduced by the loss torque, the CPU 61 corrects the target output torque calculated from the request information and the operation information, for example, by increasing the loss torque learning value. The final target output torque is determined. The loss torque learning value is updated by a loss torque learning process described later.

<Power generation control processing>
The CPU 61 controls the excitation current that flows through the alternator 47 so that the amount of power (power generation amount) generated by the alternator 47 becomes a target value. The target value of the power generation amount is determined from, for example, the power balance of the on-vehicle battery, but may be calculated by the CPU 61 or received from another electronic control device.

<Loss torque learning process>
The CPU 61 detects a crankshaft generation torque, which is a torque generated in the crankshaft 7 at the time of starting the engine 5, by an estimation calculation. It should be noted that when the engine 5 is started (hereinafter also simply referred to as starting), the cranking of the engine 5 is started and the engine 5 is completely started (the engine 5 is in a complete explosion state and the engine rotates). Period until the number reaches the idling speed).

  Then, the CPU 61 calculates the difference between the indicated torque stored in the indicated torque storage unit 62a of the ROM 62 and the detected crankshaft generation torque as the loss torque of the engine 5, and uses the calculated loss torque as the loss torque learning value. For example, it is updated and stored in the nonvolatile memory 64.

The indicated torque is a torque generated in the crankshaft 7 by combustion, and can be calculated based on the in-cylinder pressure by a measuring device on the engine bench.
In the present embodiment, the indicated torque stored in the indicated torque storage unit 62a is in a state where the cylinder intake rate is maximum (100%) (in other words, a state where the maximum air amount is put in the cylinder 55). This is a pre-measured torque. Further, the indicated torque stored in the indicated torque storage unit 62 a includes at least the maximum indicated torque Ni when the engine 5 is started.

Further, when the engine 5 is started, the engine speed once increases and then decreases to the idle speed. This increase in engine speed is called flare.
The engine speed at the start is affected by the loss torque. For example, the maximum flare value at startup (maximum value of engine speed that decreases after rising) is referred to as starting peak speed SP. The larger the torque loss, the higher the starting peak speed SP. Becomes smaller.

  Therefore, the CPU 61 detects the starting peak rotational speed SP, and calculates the crankshaft generated torque from the detected starting peak rotational speed PS. The calculated crankshaft generation torque Nc is the maximum torque generated on the crankshaft 7 when the engine 5 is started. Then, the CPU 61 uses the difference (Ni−Nc) between the maximum indicated torque Ni stored in the indicated torque storage unit 62 a and the crankshaft generated torque Nc calculated from the starting peak rotational speed SP as the loss torque of the engine 5. calculate.

  Further, in order to know the generated crankshaft torque more accurately at the start when combustion is unstable and to know the generated crankshaft torque under the same conditions as the comparison target torque, the CPU 61 starts up the engine 5. Try to maximize the cylinder intake rate. Specifically, the CPU 61 controls the throttle 41 to the open side while the engine 5 is stopped. In this example, the throttle 41 is fully opened (throttle opening = 100%) (see the period from time t1 to time t2 in FIG. 4). If the throttle 41 is open while the engine 5 is stopped, the pressure in the surge tank 52 downstream of the throttle 41 of the intake manifold 51 becomes atmospheric pressure, and the air that enters the cylinder 55 when the engine 5 is started (FIG. 2). The amount of air) is the maximum amount of air that can enter the cylinder 55. It should be noted that the throttle opening degree to be controlled while the engine 5 is stopped need not be 100%, but it is better that the throttle opening is large. In particular, if the throttle 41 is fully opened, the atmospheric pressure in the surge tank 52 can be quickly increased. Is expensive.

  Further, when the engine 5 is started, the torque Ns generated by the starter 45 is added as torque for rotating the crankshaft 7. For this reason, the torque Ns is added to the crankshaft generation torque Nc calculated by the CPU 61. Therefore, the CPU 61 also performs correction processing for correcting the calculated loss torque by an amount corresponding to the torque Ns. As the correction process, for example, after calculating the loss torque, a process of adding the torque Ns to the calculated value of the loss torque, or before calculating the loss torque, from the crankshaft generated torque Nc used for calculating the loss torque, A process of subtracting the torque Ns may be used. In both cases, the result is the same.

Based on the above, the loss torque learning process executed by the CPU 61 will be described with reference to FIG. CPU61 performs the loss torque learning process of FIG. 5, for example for every fixed time.
As shown in FIG. 5, when starting the execution of the loss torque learning process, the CPU 61 first determines whether or not the engine 5 is stopped in S210. When determining that the engine 5 is stopped, the CPU 61 controls the throttle 41 to the open side to be fully opened in the next S220, and then proceeds to S230. Note that the process of S220 has priority over the throttle control process described above. When the throttle 41 is fully opened in S220, the fully opened state continues until it is released in S240 described later.

If the CPU 61 determines in S210 that the engine 5 is not stopped (the engine 5 is in an operating state), the CPU 61 proceeds directly to S230.
In S230, the CPU 61 determines whether or not the engine 5 has been started (that is, whether or not cranking by the starter 45 has been started). In the present embodiment, since the CPU 61 controls the starter 45, for example, when the energization of the starter 45 is started, the CPU 61 determines that the start of the engine 5 is started. Further, the CPU 61 may determine whether or not the engine 5 has been started based on the crank angle signal.

  If the CPU 61 determines in S230 that the engine 5 has not started, the CPU 61 ends the loss torque learning process. For this reason, when the engine 5 is in an operating state, or when the engine 5 remains stopped, “NO” is determined in S230, and the loss torque learning process ends.

  If the CPU 61 determines in S230 that the engine 5 has started, the CPU 61 proceeds to S240 and cancels the control for fully opening the throttle 41. Then, the throttle opening is returned to the state controlled by the throttle control process.

In step S250, the CPU 61 monitors the engine speed and detects the starting peak speed SP.
Next, in S260, the CPU 61 calculates the crankshaft generation torque Nc from the starting peak rotational speed SP detected in S250. As described above, the crankshaft generation torque Nc calculated in S250 is the maximum torque generated in the crankshaft 7 when the engine 5 is started. In S260, for example, the crankshaft generation torque Nc is calculated by substituting the starting peak rotational speed SP into a calculation formula (an expression for converting the rotational speed into torque) set based on the output characteristics of the engine 5. calculate. As another example, for example, a data map for converting the rotational speed into torque may be prepared, and the CPU 61 may calculate the crankshaft generation torque Nc using the data map.

  The CPU 61 reads the aforementioned maximum indicated torque Ni from the indicated torque storage unit 62a at the next S270, and at the next S280, the difference between the maximum indicated torque Ni and the crankshaft generated torque Nc calculated at S260. (Ni-Nc) is calculated as the loss torque NL of the engine 5.

  In the next S290, the CPU 61 corrects the loss torque NL calculated in S280 by the amount of the torque Ns generated by the starter 45 at the start. Specifically, the value (NL + Ns) obtained by adding the torque Ns to the loss torque NL calculated in S280 is set as the corrected loss torque NL. The torque Ns may be a predetermined set value, for example. Alternatively, the torque Ns may be calculated from the measured value by measuring the drive current flowing through the starter 45. Further, instead of measuring the drive current of the starter 45, the battery voltage as the power source may be measured, and the torque Ns may be calculated from the measured value.

  In step S300, the CPU 61 updates and stores the loss torque NL calculated in step S290 as a loss torque learning value, for example, in the nonvolatile memory 64, and then ends the loss torque learning process.

  The process of S290 is a correction process for correcting the loss torque NL calculated in the loss torque learning process by an amount corresponding to the torque Ns. As the correction process, instead of S290, the loss torque NL is corrected in S280. A process of reducing the crankshaft generation torque Nc used for calculation by the amount corresponding to the torque Ns may be performed. Even if it deforms in this way, the result is the same.

  In the ECU 1 as described above, after the engine 5 is automatically stopped by the idle stop control, for example, when the automatic start condition is established at time t2 in FIG. 4 and the engine 5 is automatically restarted by the idle stop control, At the time of starting, the starting peak rotational speed SP is detected (S250). Then, the crankshaft generated torque Nc is calculated from the starting peak rotational speed SP (S260), and the loss torque NL of the engine 5 is calculated from the crankshaft generated torque Nc and the maximum indicated torque Ni (S270 to S290). The loss torque learning value is updated (S300). Although not shown in FIG. 4, the loss torque NL is similarly calculated and the loss torque learning value is updated not only when the engine 5 is automatically restarted but also when the user starts.

  According to such an ECU 1, since the process for learning the loss torque is performed when the engine 5 is started, it is not necessary to prohibit the automatic stop of the engine 5 by the idle stop control. For example, the dotted waveform in FIG. 4 represents the case of a conventional apparatus that performs loss torque learning during idling of the engine 5. In the conventional apparatus, even if the automatic stop condition is satisfied at time t0 in FIG. 4, until the process for learning the loss torque is completed, the automatic stop of the engine 5 is prohibited and the engine 5 is in an operating state (idle operation). State). In FIG. 4, among the periods indicated by dotted arrows, the “TLo” period is a period in which the process for learning the loss torque is performed in the conventional apparatus, and the “TSo” period uses the conventional apparatus. It is an idle stop period when there is. The period of “TSo” is shorter than the idle stop period when the ECU 1 of the present embodiment is used. Therefore, in the conventional device, the fuel consumption is deteriorated.

  On the other hand, according to the ECU 1 of the present embodiment, the execution of the idle stop control is not affected and the fuel consumption is not deteriorated. Further, according to the ECU 1, since the loss torque can be learned each time the engine 5 is automatically restarted by the idle stop control while the vehicle 3 is being used, the loss torque can be learned. Can also be secured.

  Further, the crankshaft generated torque used for calculating the loss torque may be detected by providing a torque sensor, for example. On the other hand, since the ECU 1 calculates the crankshaft generated torque based on the engine speed at the start, there is no need to provide such a torque sensor (a sensor for detecting the crankshaft generated torque).

  Further, for example, each of the illustrated torque and the crankshaft generated torque used for calculating the loss torque may be a value when a predetermined time has elapsed since the start of the engine 5 (at the start of cranking). . On the other hand, in the ECU 1, each of the illustrated torque and the crankshaft generated torque used for calculating the loss torque is set to the maximum value at the start. Specifically, the indicated torque used for calculating the loss torque is the maximum indicated torque at the start, and the crankshaft generated torque used for calculating the loss torque is also the maximum torque generated on the crankshaft 7 at the start. . For this reason, the comparison object becomes clearer, and the calculation accuracy of the loss torque is improved.

  In addition, the ECU 1 detects the starting peak rotational speed that is the maximum value of the engine speed (flare) that rises and then descends at the time of starting, and the crankshaft generated torque (that is, starting) is determined from the starting peak rotational speed. The maximum value of the crankshaft generated torque at the time). For this reason, the maximum value of the crankshaft generation torque at the time of starting can be calculated easily and accurately. For example, it is possible to monitor the increase behavior (how to increase) of the engine speed and calculate the maximum value of the crankshaft generated torque at the start from the increase behavior, but the processing is simpler than that configuration become.

  Further, the indicated torque used for calculating the loss torque in the ECU 1 is a torque measured with the cylinder intake rate being maximum. Then, by fully opening the throttle 41 while the engine 5 is stopped and maximizing the cylinder intake rate at the time of starting, the crankshaft generated torque used for calculating the loss torque is also in the state where the cylinder intake rate is the maximum. Value. For this reason, the indicated torque to be compared and the crankshaft generated torque can be set to values under the same conditions, and the crankshaft generated torque at the start when combustion is unstable can be obtained more accurately. Therefore, the loss torque calculation accuracy can be improved.

Further, since the ECU 1 increases and corrects the calculated loss torque by the amount of torque generated by the starter 45 at the time of starting, the loss torque calculation accuracy can be improved.
[Second Embodiment]
Next, the ECU according to the second embodiment will be described. As the reference numeral of the ECU, the same “1” as in the first embodiment is used. The same reference numerals as those in the first embodiment are used for the same components and processes as those in the first embodiment.

  As described above, in the ECU 1 according to the first embodiment, the throttle 41 is fully opened while the engine 5 is stopped to maximize the cylinder intake rate at the time of starting. Therefore, depending on the type of the engine 5, the flare at the time of starting is increased. The maximum value may be too large.

Considering this, the ECU 1 of the second embodiment differs from the ECU 1 of the first embodiment in the following << 1 >> and << 2 >>.
<< 1 >> The CPU 61 of the microcomputer 21 executes the blow-up suppressing process of FIG. 6 when the engine 5 is started. As shown in FIG. 6, in the blow-up suppression process, the CPU 61 controls the load torque of the alternator 47 (torque acting as a load on the crankshaft 7) to a predetermined value Ng (S310), so that the engine at the start is started. Suppresses rotation speed. The load torque of the alternator 47 can be controlled by the excitation current to the alternator 47.

  << 2 >> The CPU 61 executes the loss torque learning process of FIG. 7 instead of the loss torque learning process of FIG. The loss torque learning process of FIG. 7 differs from the loss torque learning process of FIG. 5 in that S285 is added between S280 and S290.

  As shown in FIG. 7, in S285, the CPU 61 corrects the loss torque NL calculated in S280 by the predetermined value Ng. Specifically, a value (NL−Ng) obtained by subtracting a predetermined value Ng from the loss torque NL calculated in S280 is set as a corrected loss torque NL. Then, the CPU 61 further corrects the loss torque NL calculated in S285 as described above in the next S290.

  The process of S285 is a correction process for correcting the loss torque NL calculated in the loss torque learning process by a reduction amount corresponding to the load torque (predetermined value Ng) of the alternator 47. As the correction process, the process in S285 is performed. Instead, a process of increasing the crankshaft generation torque Nc used for calculating the loss torque NL by a predetermined value Ng in S280 may be performed. Even if it deforms in this way, the result is the same. As another modification, the process of S285 may be performed after S290.

According to the ECU 1 of the second embodiment as described above, it is possible to ensure good calculation accuracy of the loss torque while suppressing excessive flare at the time of starting.
As mentioned above, although embodiment of this invention was described, this invention can take a various form, without being limited to the said embodiment. The above-mentioned numerical values are also examples, and other values may be used.

  For example, in the above embodiment, the transmission 9 of the vehicle 3 is an automatic transmission, and the shift range of the transmission 9 is considered to be the drive range (D range) when the engine 5 is automatically started by idle stop control. It is done. For this reason, if it is desired to obtain a value excluding the torque loss due to the transmission 9 (hereinafter referred to as transmission loss torque) as the loss torque of the engine 5 calculated by the loss torque learning process at the time of automatic start of the engine 5, What is necessary is just to comprise.

  That is, a value obtained by subtracting the transmission loss torque from the loss torque NL calculated in S290 of FIGS. 5 and 7 may be a finally calculated loss torque. As the transmission loss torque used for the subtraction, for example, a constant value obtained experimentally may be used, or depending on the engine coolant temperature, oil temperature, ATF (automatic transmission fluid) temperature, outside temperature, etc. It may be variably set.

  In addition, the functions of one component in the above embodiment may be distributed as a plurality of components, or the functions of a plurality of components may be integrated into one component. Further, at least a part of the configuration of the above embodiment may be replaced with a known configuration having the same function. Moreover, you may abbreviate | omit a part of structure of the said embodiment as long as a subject can be solved. In addition, all the aspects included in the technical idea specified by the wording described in the claims are embodiments of the present invention. In addition to the ECU described above, the present invention is realized in various forms such as a system including the ECU as a constituent element, a program for causing a computer to function as the ECU, a medium storing the program, and a learning method for loss torque. You can also.

  3 ... Vehicle, 5 ... Engine, 61 ... CPU of microcomputer, 62a ... Illustrated torque storage section of ROM

Claims (6)

A vehicle (3) provided with idle stop control means (61, S110 to S160) for automatically stopping the engine (5) when a predetermined automatic stop condition is satisfied and then automatically starting the engine when a predetermined automatic start condition is satisfied. ), An engine loss torque learning device for learning the engine loss torque,
Illustrated torque storage means (62a) for storing the indicated torque of the engine at the time of starting the engine;
Torque detecting means (61, S250, S260) for detecting crankshaft generated torque, which is torque generated on the crankshaft of the engine at the time of starting the engine;
Loss torque calculation means (61, S270 to S290) for calculating a difference between the indicated torque stored in the indicated torque storage means and the generated crankshaft torque detected by the torque detection means as a loss torque of the engine. When,
Equipped with a,
The indicated torque is the maximum indicated torque at the start of the engine,
The crankshaft generated torque detected by the torque detecting means is a maximum torque generated in the crankshaft when the engine is started;
Engine loss torque learning device according to claim. The engine loss torque learning device according to claim 1 ,
The torque detection means is a means for detecting by calculating the crankshaft generated torque, and at the time of starting the engine, detects the peak rotational speed at startup which is the maximum value of the engine rotational speed that rises and then falls. Calculating the crankshaft generation torque from the detected starting peak rotational speed,
An engine loss torque learning device. A vehicle (3) provided with idle stop control means (61, S110 to S160) for automatically stopping the engine (5) when a predetermined automatic stop condition is satisfied and then automatically starting the engine when a predetermined automatic start condition is satisfied. ), An engine loss torque learning device for learning the engine loss torque,
Illustrated torque storage means (62a) for storing the indicated torque of the engine at the time of starting the engine;
Torque detecting means (61, S250, S260) for detecting crankshaft generated torque, which is torque generated on the crankshaft of the engine at the time of starting the engine;
Loss torque calculation means (61, S270 to S290) for calculating a difference between the indicated torque stored in the indicated torque storage means and the generated crankshaft torque detected by the torque detection means as a loss torque of the engine. When,
With
The indicated torque is a torque measured at a maximum cylinder intake rate,
Adjusting means (61, S220) for maximizing the cylinder intake rate when starting the engine by controlling the throttle (41) of the engine to the open side while the engine is stopped;
An engine loss torque learning device. In the engine loss torque learning device according to claim 3 ,
Control means (61, S310) is provided for controlling the load torque of the alternator driven by the engine to a predetermined value to suppress the engine speed from rising when the engine is started.
The loss torque calculating means has a function of correcting the loss torque to be calculated by reducing the predetermined value by the predetermined value (S285).
Engine loss torque learning device according to claim. A vehicle (3) provided with idle stop control means (61, S110 to S160) for automatically stopping the engine (5) when a predetermined automatic stop condition is satisfied and then automatically starting the engine when a predetermined automatic start condition is satisfied. ), An engine loss torque learning device for learning the engine loss torque,
Illustrated torque storage means (62a) for storing the indicated torque of the engine at the time of starting the engine;
Torque detecting means (61, S250, S260) for detecting crankshaft generated torque, which is torque generated on the crankshaft of the engine at the time of starting the engine;
Loss torque calculation means (61, S270 to S290) for calculating a difference between the indicated torque stored in the indicated torque storage means and the generated crankshaft torque detected by the torque detection means as a loss torque of the engine. When,
With
The loss torque calculation means has a function of correcting the increase of the loss torque to be calculated by an amount corresponding to the torque generated by the starter when the engine is started (S290).
An engine loss torque learning device. In the engine loss torque learning device according to any one of claims 1 and 3 to 5 ,
The torque detecting means is a means for detecting by calculating the crankshaft generated torque, and calculating the crankshaft generated torque based on an engine speed at the start of the engine;
An engine loss torque learning device.